John Gill's Exposition of the Whole Bible
Psalms 119:66
Teach me good judgment and knowledge,.... Or, "a good taste" p: of the Lord himself, how good and gracious he is; of his grace and love, which is better than wine; of his word and the truths of it, which are sweeter to a spiritual taste than honey or the honeycomb; and of the things of the Spirit of God, which are seventy to a spiritual man, a distinguishing taste of things; for as "the taste discerns perverse things" in food, so a man of a spiritual taste distinguishes good from evil, truth from error; discerns things that differ, and approves of those that are most excellent, and abides by them. Or, "a good sense" q, as it may be rendered; a good sense of the Scriptures, the true and right sense of them; and to have the mind of God and of Christ, and of the Spirit of Christ, in the word; and to have distinguishing light in it, and a well established judgment in the truths of it, is very desirable: as is also a spiritual and experimental "knowledge" of them, a growing and increasing one; a knowledge of God in Christ, and of his will; a knowledge of Christ, his person and offices, and the mysteries of his grace; which a truly gracious and humble soul desires to be taught, and is taught of God more or less;
for I have believed thy commandments; the whole word of God, and all that is said in it; that it is of God, is the word of God and not the word of man; and therefore he was desirous of being taught the true meaning of it, and to be experimentally acquainted with it; the word of God is called his commandment, Psalms 19:7. Or the precepts of the word; he believed these were the commandments of God, and not of men; delivered out by him, and enforced by his authority; and therefore he gave credit to them, and loved them, and desired better to understand and do them: or the promises and threatenings annexed to them, which he believed would be punctually fulfilled upon the doers or transgressors of them; and as for himself, he cheerfully yielded the obedience of faith unto them.
p טוב טעם "bonitatem gustus", Piscator, Michaelis. q "Bonitatem sensus", Montanus; i.e. "sensum bonum", Gejerus.